WASHINGTON — President Biden’s cabinet took steps toward belated completion on Tuesday with the confirmation of a United Nations ambassador and an agriculture secretary, but other top posts remained locked in partisan confirmation hearings.
The race to question prospective cabinet officials led to overlapping hearings throughout the morning, as Democrats labored to staff key roles that most of Mr. Biden’s predecessors had filled much earlier in their first terms.
The Senate voted to confirm Linda Thomas-Greenfield as the U.N. ambassador and Thomas J. Vilsack as the secretary of agriculture. Both Ms. Thomas-Greenfield and Mr. Vilsack were confirmed by comfortable margins, with Mr. Vilsack clearing 92 to 7 to become the agriculture secretary for the second time.
Earlier in the day, the Senate Judiciary Committee wrapped up a second day of questioning Mr. Biden’s attorney general nominee, Merrick B. Garland. Mr. Garland’s hearing was again predominantly civil and straightforward, with members of both parties continuing to strike the same deferential tone they set in praising his qualifications on Monday.
The atmosphere was less easygoing in other committee rooms.
Representative Deb Haaland of New Mexico, Mr. Biden’s pick for interior secretary, faced a litany of questions over the fierce stance she has taken in the past against fossil fuels, particularly by senators from states still reliant on fossil fuel extraction.
Key among them was Senator Joe Manchin III of West Virginia, the chairman of the Senate Energy and Natural Resources Committee, who has resisted efforts to scale down coal production in his state, and whose vote may be crucial to Ms. Haaland’s chances of confirmation.
Democrats stressed the historic nature of her nomination — one Mr. Manchin acknowledged. If confirmed, Ms. Haaland would be the first Native American to lead a cabinet-level department, in this case the Interior Department, which has abused and neglected Indigenous Americans for much of the nation’s history.
Ms. Haaland sought to play down her past activism, pledging to follow the Biden administration’s policy priorities.
“If I’m confirmed as secretary, it’s President Biden’s agenda, not my own agenda, that I would be moving forward,” she said.
She will appear before the committee for a second day on Wednesday.
Tuesday also marked the first of two challenging confirmation hearings for Xavier Becerra, the attorney general of California and Mr. Biden’s nominee for secretary of health and human services.
In contentious questioning, Republican members of the Senate Health, Education, Labor and Pensions Committee sought to portray Mr. Becerra, who has little experience in public health, as unqualified, while painting his positions on abortion and health care as radical.
Mr. Becerra, who will lead an extensive coronavirus vaccination effort if confirmed, said he sought to focus on the country’s most immediate challenges stemming from the pandemic and find opportunities to compromise on more politicized health policies.
“When I come to these issues, I understand that we may not always agree on where to go,” he said, “but I think we can find some common ground.”
Mr. Becerra will face another round of questioning from the Senate Finance Committee on Wednesday.
On Tuesday, the Finance Committee also convened a confirmation hearing for Adewale O. Adeyemo, Mr. Biden’s pick to serve as deputy Treasury secretary.
The steady beat of hearings helped make up for lost time for senators who spent six days this month focused entirely on former President Donald J. Trump’s impeachment trial.
It also cleared the way for senators to consider even more nominees this week. On Wednesday, senators will take up William J. Burns’s nomination to lead the Central Intelligence Agency, and on Thursday they will turn to Katherine C. Tai’s nomination to serve as the United States trade representative.